Arrays of many pipes, their keying actions, enclosures, and wind sources lend pipe organ sound at least twenty-six properties which distinguish it from the sound of most prior art electronic organs (cf. William D. Turner, Basic musical differences between pipe organs and contemporary electronic organs. Laurel, Md., 1979). Of eight electronic organs in the prior art, thirteen duplicate only a single property, four duplicate only six properties, and only one duplicates as many as nine properties. One digital organ in the prior art (cf. Deutsch: U.S. Pat. No. 3,515,792), which is said to be "capable of reproducing accurately all of the . . . tonal qualities of an air driven pipe organ", actually duplicates only one of the twenty-six properties of pipe organ sound. Another prior art electronic organ which contained hundreds of individual tone frequency oscillators did not prove competitive with pipe organs and other electronic organs. The prior art actually discloses no practical electronic equivalent of pipe organs' many individual tone sources. Such sources are quite numerous as a rule, individual in waveform, independent in phase, variously responsive to keying, spatially dispersed, variously decoupled acoustically, and in various degrees of optimal mistune. Most prior art electronic organs employ only twelve basic tone sources whose frequencies are exactly divided to generate different octaves. The resulting tone currents are then variously waveformed to produce nominally different organ voices. The integral relations between the tone current frequencies for different octaves, the identities of corresponding frequencies in the different voices, and the monophonic circuitry and sound systems employed in such prior art organs, together preclude the distinctive identities of concurrently sounding octaves or voices, and the particular resulting chorus and related effects, which together are characteristic of pipe organs. None of the means for simulating or approximating such characteristics, which some prior art electronic organs employ, duplicates the effects of pipe organs.